How do reference types differ from value types, and how does this affect working with them?

In C#, there are two main data types: reference types and value types.

• Value types:

  • Store data directly.
  • Examples: int, double, struct, bool.
  • Assigning copies the value.
  • Stored on the stack (in most cases).

• Reference types:

  • Store a reference to the memory location where data is held.
  • Examples: class, string, array.
  • Assigning copies the reference, not the data itself.
  • Stored on the heap.

Impact on operation:

• Changes in a reference type object are reflected in all references to it.
• Value types are copied when passed to methods, so changes inside the method do not affect the original.
• Memory management for reference types is handled by the garbage collector.

Example:

int a = 5;
int b = a; // copy of the value
b = 10;
// a remains 5

class Person { public string Name; }
Person p1 = new Person { Name = "Alice" };
Person p2 = p1; // copy of the reference
p2.Name = "Bob";
// p1.Name is now "Bob"